Shares of Halliburton Co. stock (NYSE: HAL) were up nearly 4 percent shortly after 9 a.m. on Friday, hours after reports emerged that the company had admitted to destroying evidence in the case of the Deepwater Horizon BP oil spill.

Late Thursday, the Department of Justice published documents that showed a Halliburton cementing technology director had ordered an employee to destroy the results of a computer simulation. The simulation had tested the safety of the drill set-up at the Macondo well, and the importance of a certain drilling device called a centralizer.